In 2010, Stuxnet, a computer malicious worm, hacked into the control system of Iran's Bushehr nuclear power plant via an infected USB flash drive. Exploiting “zero-day” vulnerability, it infected with the project files of Siemens control software. Through modifying the user program in the PLC (Programmable Logic Controller) connected to the infected host, it dramatically changed the controlled centrifuge spinning, which led to damage to the machine and improper running of the nuclear facilities. PLC, as a core control unit of industrial control systems, of its security, directly determines the normal and stable operation of industrial control systems. After Stuxnet, PLC's security becomes a focus of the industry.
The existing test methods for PLC security defense device only test on corresponding defense rules of the PLC security defense device, with simpler test means that cannot comprehensively test on the security features of the device.